A voltage regulator can typically include an output filter having an output inductor for connection to a load and an output capacitor in parallel with the load. The output inductor is connected to and disconnected from an input voltage by switching high side and low side power transistors to regulate an output voltage of the voltage regulator. The switching induces a ripple in inductor current of the voltage regulator, which manifests itself in the output voltage due, principally, to equivalent series resistance (ESR) in the output capacitor.
In many applications, the ripple in the inductor current constitutes noise which must be minimized. However, certain voltage regulator designs regulate the output voltage based on the ripple in the output voltage. Some of these voltage regulator designs may not operate stably when the ripple in the output voltage is too small. Others may operate stably, but require a relatively constant series resistance of the output inductor as well as additional components. These additional components must be external to an integrated circuit that houses remaining components of the voltage regulator.